I. Field
The present disclosure relates generally to electronics, and more specifically to techniques for controlling an oscillator.
II. Background
Oscillators are an integral part of many electronics circuits and are particularly important in communication circuits. For example, transmitters and receivers use local oscillator (LO) signals for frequency upconversion and downconversion, respectively. The LO signals are typically generated with oscillators.
An oscillator may have an oscillation frequency that may be varied with a control signal. The oscillator may be characterized by a tuning function, which is a function of the oscillation frequency versus the control signal. For a linear tuning function, the oscillation frequency varies linearly with the control signal. A linear tuning function may be desirable if a signal generated by the oscillator is modulated with data. However, the tuning function of the oscillator is typically not linear, and tuning nonlinearity refers to deviations of the tuning function from a linear function. The tuning nonlinearity may degrade the quality of a modulated signal and adversely impact performance.